Clinical Application of Stroke- Oyawusi Flashcards
What is the difference between ischemic and hemorrhagic stroke?
- ischemic stroke results from occlusion of cerebral vessels
- hemorrhagic stroke results from rupture of cerebral vessels
- ischemic is the most common (80%)
- stroke is the fifth leading cause of death in US
What are the modifiable risk factors?
things people can amend by taking medications of changing lifestyle that increase changes of stroke or recurrence
- hypertension
- diabetes
- heart disease
- dyslipidemia
- atrial fibrillation
- carotid artery disease
- obstructive sleep apnea, hematological disorders, drug abuse (especially cocaine), cigarette smoking, excessive alcohol intake, obesity, oral contraceptive use (especially those with estrogen)
What is one big fact to know regarding causes for stroke?
33-40% of strokes involves large vessel occlusions!!
87% of strokes are of what type and what are they characteristic of? What about 13% of strokes?
87% is ischemic
- cardioembolic
- large vessels
- small vessels
13% is hemorrhagic
- intracerebral hemorrhage (bleeding into the parenchyma)
- subarachnoid hemorrhage
What are a non modifiable risk factor for stroke?
-AGE: stroke rises with age (over the age of 75- 12.7 men and 10.7 women will have stroke)
-GENDER
RACE/ETHNICITY
FAMILY HISTORY OF STROKE
PRIOR STROKE, TIA, HEART ATTACK
What are the risk factors of stroke for women?
- hypertension
- migraine with aura
- atrial fibrillation
- diabetes
- depression
- emotional stress
- post menopausal state and hormonal status
- pregnancy, childbirth, and pre-eclampsia
How do you recognize stroke/TIA when it comes into the ER? What are the symptoms?
SUDDEN ONSET of neurological deficits
- focal weakness
- focal sensory disturbances
- loss of vision in one eye or visual field
- speech disturbances
- vertigo: dizziness with rotational component
- ataxia: gait imbalance
- diplopia: double vision
What is the acronym used to deal with a stroke?
TIME IS OF THE ESSENCE!!!! (FAST)
F ace drooping on one side
A rm weakness on one side
S peech jumbled, slurred, or lost
T ime to call 911
How do you rule out a hemorrhagic stroke? What test do you perform?
head CT (non-contrast)
-if there is no hypodensity on the head CT patient can be given tPA which is one of things to treat pt with an ischemic stroke acutely
bright white on a head CT is fresh blood
What should consist of the evaluation for stroke/TIA?
- history for time of onset of symptoms, predisposing factors
- vital signs and state of consciousness (are they awake or alert enough to protect their airway)
How do you a stroke is localized to the right brain?
Right brain: right gaze (left frontal eye field is intact pushing the eyes to the right), left hemineglect (if the right parietal region is involved), left hemisensory (visual/ tactile, or auditory stimuli), left hemiparesis, left hemianopsia
How do you a stroke is localized to the left brain?
Left brain: left gaze, right hemiparesis, right hemisensory, right hemianopsia, aphasia (Broca’s (decreased speech production, problem with fluency, exchange words like dork for fork), expressive, receptive)
-if temporal lobe was affected it would be Wernicke’s problem understanding speech, word salad nonsensical speech
How do you a stroke is localized to the brainstem?
Brainstem: CROSSED SIGNS; cranial nerves: diplopia, facial weakness, vertigo, tinnitus swallowing problems, hiccups, vomiting; Quadriparesis or hemiparesis
How do you a stroke is localized to the cerebellum?
cerebellum: ataxia, imbalance, incoordination
What are symptoms for stroke involving middle cerebral artery?
superficial aphasia, hemineglect, contralateral hemiparesis, sensory deficit of face, arm
What are symptoms for stroke involving anterior cerebral artery?
involving the leg fibers in the homunculus
-contralateral leg weakness and sensory deficit
What are symptoms for stroke deep within the hemisphere?
contralateral hemiplegia, hemisensory deficit, homonymous hemianopsia
What are symptoms for stroke involving posterior cerebral artery?
contralateral homonymous hemianopsia, visual agnosia, prosopagnosia (in temporal lobe specifically), simultanagnosia (lesion in occipital lobe associated with the temporal lobe; cannot identify any object)
What are symptoms for stroke involving vertebrobasilar artery especially PICA?
-lateral medullary syndrome (Wallenburg syndrome): VASST
-vestibular: ataxia, dizziness
-ambiguus: hoarseness, dysphagia
-sympathetic: Horner’s syndrome
Spinothalamic tract: deficits with picking up pain and temperature
-crossed clinical syndromes, ataxia, vertigo, diplopia
What does hypodensity mean on a head CT for a patient coming in with stroke symptoms?
- that identifies an area of infarction
- this means the pt cannot be given tissue plasminogen activator (tPA)
- the tissue (very friable and delicate) would be at risk for hemorrhage if we give them antiplatelet therapy
- ideally you would want a clean head CT to give tPA
bleeding would be hyperdensity
Why is time of the essence when it comes to strokes?
for every minute after stroke the brain loses:
- 1.9 million neurons
- 14 billion synapses
- 7.5 miles myelinated fibers
What is tPA and what is its function?
- Tissue plasminogen activator
- breaks up clots
- pt should receive this medication within 3 hours of the onset of symptoms (if not risks of giving medication outweigh benefits)
- physician should try to achieve a door to needle time within 60 minutes in at least 50% of ischemic stroke patients treated with IV tPA
- tPA does not reverse
Who is intravenous rt-PA is recommended for?
recommended for selected patients who may be treated within 3 hours of onset of ischemic stroke
What is the thrombolytic therapy checklist?
≥18 years of age with ischemic stroke < 3 hours
Deficit found to be potentially disabling; severity quantified with NIH stroke scale (0 - 42 scale)
figure out the coagulation status; find if they are on anticoagulants (Warfarin or Plavix)
test INR (which should be ≤ 1.7) and normal PTT
measure platelet level which should be > 100,000
blood pressure SBP < 185 mm Hg, DBP < 110 mm Hg
glucose > 50 mg/dL
no evidence of intracranial hemorrhage on pretreatment CT
clinical presentation is suggestive of a subarachnoid hemorrhage
NO active internal bleeding of any kind in the body (vaginal, etc.)
no intracranial surgery or trauma or previous stroke
On repeated measurements, SBP greater than 185 mm Hg or DBP greater than 110 mm Hg at the time treatment is to begin.
NO history of intracranial hemorrhage or Known arteriovenous malformation, or aneurysm
If a patient went to bed at 10 pm the night before perfectly but woke up at 7 am experiencing stroke like symptoms, would you give them tPA?
no because the onset of symptoms is ambiguous
Once the patient comes in to the ER, what is the time frame that they should be seen and by whom? What should be done?
- within 10 minutes preferably by a neurologist
- plain head CT (to rule out bleed, hypodensity, or a large infarct); contrast to look at BVs
not MRI because it takes about 45 minutes
neurologist would have read T and ideally within an hour the pt would receive tPA if CT is clean
What are the two scales used to note what the patient’s deficits are?
modifying ranking score (prestroke mRS should be between 0 and 1)
0= completely independent and can take care of themselves 5= nursing; will be less likely to be sent for a thrombectomy
NIH stroke scale (should be at least a 6)
63 year old female with h/o ischemic cardiomyopathy (ICM), congestive heart failure (CHF) with left ventricular assist device (LVAD) with INR of 2.2 who presented with RMCA syndrome.
NIHSS: 21
Last known well: 4: 00 pm
Arrival Date/Time: 6:05 pm
Is she a candidate for tPA?
NOOOO her INR is too high
but you can do a thrombectomy (NIHSS is >6 meaning she has a lot of deficits and a large artery is involved)
-do the CT angiogram of head and neck
Time to IR Suite: 6:35 pm Groin Puncture Time: 7:05 pm First Pass with Catheter: 7:11 pm Recanalization Time: 7:33 pm TICI
NIHSS at 24 hours: 9
Patient discharge to acute rehab in 4 days
Once someone has a stroke they are at risk for having another one. What are some measures the patient should be advised to take?
- place pt on appropriate hypertensives
- appropriate antilipidemic agent (statin)
- glucose is controlled well
- lifestyle changes( stop smoking, drinking)
What are the causes of ischemic strokes?
large vessel disease:
- cervical, within the neck the internal carotid arteries could be blocked
- intracranial arteries can be blocked
small vessel disease:
- can occur if pt has hypertension
- cardioembolic: arrhythmia like atrial fibrillation; increased risk of formation of a thrombus that could break up into chunks and form and emboli
-other less causes: arteritis, dissection (especially carotid), sickle cell fibromuscular, dysplasia, hypercoagulable state
What are watershed strokes? KNOW THIS
strokes that occur in between vascular territories and tend to be cortical
due to dectreased perfursion
What are lacunae infarctions?
- cause small vessel disease
- due to hardening of arteries
- due to dyslipidemia, calcification of arteries etc.
Define TIA.
transient ischemic attack
- occurs because there is decreased perfusion to an area but its not complete like an infarct or occlusion
- a majority of TIA do not have neuroimaging signs
-most TIA are stroke like symptoms that occur within less than an hour
the time cut off for symptoms is one hour
Why do we use tPA for patient who do not have a clot in the major artery?
it is a clot buster; it is a major blood thinner
need to have < 185/110
What is the EXPRESS study?
Oxford, England - introduction of daily TIA/minor stroke clinic (what we should for pts with a TIA)
- Median delay in assessment fell from 3 days to 1 day
- Median delay to first prescribed treatment fell from 20 days to 1 day
- The 90 day stroke risk fell from 10.3% to 2.1%.
- they saw that having a delay in the assessment fell from 3 to 1 days
- improved how the clinicians assess the patients when they started interventions
When is MRI most appropriate to use according to AHA ASA?
- when you’re doing neuroimaging to evaluate stroke especially the DWI for acute lesion
- one of the MRI sequences
- used to evaluate for acute and older lesions/strokes
- DO NOT give to pts with metal in their body (defibrillator/pacemakers)
but do a CT when pt first comes in remember time is of the essence
Why should non-invasive imaging of cervical vessel be performed routinely?
along with the CT scan you get to the CTA to look at vessels in the head and neck
-if the pt may be a candidate for a thrombectomy
-a subacute intervention
carotid endarterectomy or carotid stents
What percentage of occlusion needs to be present for carotid endarterectomy?
70-90% occlusion of the affected carotid artery
Why is an ECG performed?
- to make sure there is no clot in any of the ventricles
- to look for atrial fibrillation which is one of the risk factors for stroke
In the ECG look for:
- PFO (TTE bubble study, TEE, or TCD)
- Aortic arch atherosclerosis (TEE)
- Valvular disease (TEE)
KNOW THIS: Only if cryptogenic: hypercoagulable evaluation. Why?
if the patient is young and without the usual risk factors (Cryptogenic); maybe they have a genetic predisposition so you do a hypercoagulable test
Secondary prevention of stroke is important/key because once someone has a stroke, they are at risk of having it again. What are the medical interventions?
antiplatelet therapy usually aspirin and other things:
- aspirin (doses 81-325)
- Clopidogrel
- Aspirin + clopidogrel
- Aspirin + dipyridamole
What is the overall goal of antihypertensive therapy, Hb A1c, cholesterol (LDL, give statin) ?
BP <130/80
HbA1c ≤ 7
LDL goal <100 for those without DM, but with DM as a comorbidity <70
When would you do a carotid stenosis?
- CEA urgently (carotid endarterectomy)
- not just if they have stroke on affected side but they have symptoms of TIA that correlate with narrowing of the artery
What are the areas of the brain that you are at highest risk to see intracranial hemorrhage due to hypertension?
- Basal Ganglia (KNOW THAT THIS IS NUMBER ONE especially putamen)
- Thalamus
- Centrum Semi-ovale
- Pons
- Cerebellum – Neurosurgical Emergency
What are the classical symptoms for intracerebral hemorrhage?
- Sudden Severe headache
- Altered Sensorium
- Focal Neurological Deficit depending on location of hemorrhage
The location of the subarachnoid hemorrhage are usually where?
85% Subarachnoid space (Circle of Willis)
15% Sylvian fissure – MCA trifurcation
About 7% of strokes secondary to aneurysmal rupture. What vessels are at risk of aneurysms?
due to small vessels that have branch
What are the symptoms of subarachnoid hemorrhage?
no focal neurological deficits (unlike intracerebral hemorrhage)
Sudden Severe Headache!!!!
Altered Sensorium
No focal neurological deficit
Signs of meningeal irritation – neck stiffness, Brudzinski’s sign, Kernig’s sign
Oculomotor Nerve at onset of headache – Ipsilateral Posterior Communicating artery aneurysm rupture
KNOW THAT the first signs of rupture or aneurysm of Ipsilateral Posterior Communicating artery
ptosis, then wide eye (dilated pupil) because
the oculomotor controls the ciliary muscle which dilate
What are neurological complications of strokes/TIA?
- Progression of thrombosis
- Recurrent embolism
- Brain edema
- Hydrocephalus (SAH)
- Increased Intracranial Pressure
- Hemorrhagic Transformation (the tissue very friable and delicate would be at risk for hemorrhage if we give them antiplatelet therapy)
- Seizures are positive symptoms (strokes are negative symptoms)
What are the medical complications that can occur with stroke/TIA?
- Pneumonia
- Airway Obstruction
- Hypertension
- Bladder Infections
- Depression
- Electrolyte Disturbances
- Myocardial Infarction
- Congestive Heart Failure
- Cardiac Arrhythmias
- Deep Vein Thrombosis
- Pulmonary Embolus
- GI Bleeding (any bleeding diathesis)
